File organization on direct access  disk device

ABSTRACT

A TECHNIQUE IS DISCLOSED FOR UTILIZING ALL AVAILABLE WORK SPACE ON DIRECT ACCESS DISK DEVICES WITHOUT REGARD TO THE   A LOGICAL ADDRESS NAMING CONVENTION FOR AVAILABLE WORK SPACE AND AN AUTOMATIC TRANSLATION OF PHYSICAL ADDRESS TO   LOGICAL ADDRESS. THE TRANSLATION IS AUTOMATICALLY MACHINE CALCULATED ACCORDING TO   M=MMM(V) H=HHH(V)+XX-VVV(V) C=CCC(V)+YY XX=FLOOR(RT//(TPC.NWK)) YY=FLOOR(RT/(TPC.NWK))   WHERE M IS THE PHYSICAL MODULE NUMBER, H IS THE PHYSICAL TRACK (HEAD) NUMBER, C IS THE PHYSICAL CYLINDER NUMBER, MMM, HHH, AND CCC ARE PHYSICAL MODULE, HEAD AND CYLINDER NUMBERS AT PREDETERMINED BREAK POINTS SELECTED BY THE USER, XX AND YY ARE PARAMETERS, AND X IS A PARAMETER EQUAL TO THE LOWEST POSSIBLE VALUE OF V AT WHICH VVV(V) $XX$WWW(V) WHERE VVV IS EQUAL TO THE FIRST LOGICAL TRACK OF A GROUP AND WWW IS EQUAL TO THE LAST LOGICAL TRACK OF THAT GROUP, A GROUP COMPRISING ALL LOGICAL TRACKS BETWEEN TWO OF THE PREDETERMINED BREAK POINTS, AND WHERE A BREAK POINT IS THE TRANSFER FROM ONE PHYSICAL CYLINDER TO ANOTHER PHYSICAL CYLINDER. A TRACK INTERLEAVING TECHNIQUE IS ALSO DISCLOSED FOR COMBINATION WITH THE WORK SPACE TECHNIQUE TO ACHIEVE RAPID COMPARISON OF PARALLEL FILES.

v UNITED STATES PATENT OFFICE Published at the request of the applicant or owner in accordance with the Notice of Dec. 16; 1969, 869 687. The abstracts of Defensive Publication applications are identified by distinctly numbered series and are arranged chronologically- The heading of each abstract indicates the number of pagesof specification, including claims and sheets of drawings contained in the application as originally filed. The files of these appllcationsare available to the public for inspection and reproduction may be purchased for 30 cents a sheet.-

Defensive Publication applications have not been examined as to the merits of alleged invention. The Patent Ofllce makes no assertion as to the novelty of the disclosed subject matter.

PUBLISHED JULY 2, 1974 FILE ORGANIZATION ON DIRECT ACCESS DISK DEVICE Leslie S. Coleman, Jr., Poughkeepsie, N.Y., assignor to International Business Machines Corporation, Annonk,

Continuation of application Ser. No. 199,692, Nov. 17, 1971. This application Oct. 2, 1973, Ser. No. 402,694 Int. Cl. G06f 9/06, 13/04 U.S. Cl. 340-1725 5 Sheets Drawing. 20 Pages Specification A technique is disclosed for utilizing all available work space on direct access disk devices without regard to the actual physical location of the work space by providing ADDRESS WNVERT RT l0 uca g. ,400 (RT/TPOl/INIIK C-FLOOREll/(TPC-Nlliil-HGUU] A RETURN 405 ADDRESS WNVERT RI T0 llOll 0 mm an? mmn ,soi mun RETURN a logical address naming convention for available work space and an automatic translation of physical address to Kill-ill logical address. The translation is automatically machine calculated according to where -M is the physical module number, H is the physical track (head) number, C is the physical cylinder number, MMM, HHH, and CCC are physical module, head and cylinder numbers at predetermined break points selected by the user, XX and YY are parameters, and X is a parameter equal to the lowest possible value of V at which VVV(V) sXXsWWWW) where VVV is equal to the first logical track of a'group and W is equal to I the last logical track of that group, a group comprising all logical tracks between two of the predetermined break points, and where a break point is the transfer from one physical cylinder to another physical cylinder.

A track interleaving technique is also disclosed for combination with the work space technique to achieve rapid comparison of parallel files.

July 2, 1974 L. S- COLEMAN, JR

FILE ORGANIZATION 'ON DIRECT ACCESS DISK DEVICE Original Filed Nov. 17, 1971 FIG. 3

ADDRESS CONVERT RT T0 MCH 5 Sheets-Sheet 3 (RT TPC) I/NWK 0= FLOOR /(TPC NWK 00 (M [I RETURN FILE ORGANIZATION 0N DIRECT ACCESS DISK DEVICE Original Filed Nov. 17 1971 5 Sheets-Sheet 5 FIG. 4

ADDRESS CONVERT RT T0 MCH 505 [RT HH (m1 TPC NWK 506 M RT 2 HH (M H= TPC M RT 2 HH (M 50? c FLOOR cc (M) TPC --w| RETURN FILE ORGANIZATION ON DIRECT ACCESS msx DEVICE Original Filed Nov. 17, 1971 July 2, 197 1.. s. COLEMAN, JR

5 Sheets-Sheet L FIG. 5

TPC 20 HH()= CC (0 1 2 HH 2) 4 CC (2) 1 TPC NWK=60 OEJ 1 July 2, 1974 L. s. COLE-MAN, JR

FILE ORGANIZATION on DIRECT ACCESS DISK DEVICE 5 Sheets-sheet 5 Original Filed Nov. 17, 1971 HHH CCC

MMM

WWW

VVV

FIGS

HHH

MMM

WWW

VVV

ADDRESS FIG.8

CONVERT RT T0 MCH 

